Two farmers in South Africa captured the incredible moment a high-speed asteroid the size of a car exploded before hitting the Botswana savannah.

The footage was posted to Facebook by farmer Barend Swanepoel at 6.40pm and shows the asteroid quickly approaching his farm at Ottosdal—near the border with Botswana at 6.40 pm.

The farmer said he was driving home from his neighbours when he saw the “huge fireball” in the sky.

“The advantage I had was I saw it in colour and it was not like on the cameras. It was a fireball falling with this red tail behind and I thought that the grassland is going to burn,” said Mr Swanepoel.

The massive space rock was discovered by NASA eight hours before it hurtled down from the sky and blew up 30 miles before impact.

NASA’s asteroid trackers quickly determined the six foot wide rock was not large enough to pose a serious threat to Earth. While the asteroid did not present any danger, NASA officials have said the experience was a good training exercise for scientists and asteroid observers.

NASA’s planetary defence officer said in a statement: “This was a much smaller object than we are tasked to detect and warn about. However, this real-world event allows us to exercise our capabilities and gives some confidence our impact prediction models are adequate to responde to the potential impact of a larger object.”